[PATCH v8 1/2] format-patch: make newline after signature conditional

[Jeremiah Mahler <jmmahler@gmail.com>]

From: Jeff King <peff@peff.net>

When we print an email signature, we print the divider "--
\n", then the signature string, then two newlines.
Traditionally the signature is a one-liner (and the default
is just the git version), so the extra newline makes sense.

But one could easily specify a longer, multi-line signature,
like:

  git format-patch --signature='
  this is my long signature

  it has multiple lines
  ' ...

We should notice that it already has its own trailing
newline, and suppress one of ours.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Jeremiah Mahler <jmmahler@gmail.com>
---
 builtin/log.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/builtin/log.c b/builtin/log.c
index 39e8836..5acc048 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -844,8 +844,13 @@ static void gen_message_id(struct rev_info *info, char *base)
 
 static void print_signature(void)
 {
-	if (signature && *signature)
-		printf("-- \n%s\n\n", signature);
+	if (!signature || !*signature)
+		return;
+
+	printf("-- \n%s", signature);
+	if (signature[strlen(signature)-1] != '\n')
+		putchar('\n');
+	putchar('\n');
 }
 
 static void add_branch_description(struct strbuf *buf, const char *branch_name)
-- 
Jeremiah Mahler
jmmahler@gmail.com
http://github.com/jmahler